Abstract:
Sex identification is a primary step in forensic analysis of skeletal remains. The accuracy of sex estimation methods greatly depends on the sexual dimorphism manifested by the target anatomical region. The study aims to evaluate the sexual dimorphism in shape and size of the neurocranium and to compare the potential of shape and size of different cranial regions to classify correctly the male and female crania. The study was carried out on computed tomography images of 373 Bulgarian adults (161 males and 212 females). Three-dimensional coordinates of 32 landmarks were acquired. The landmarks were arranged in 4 configurations: neurocranium, frontal bone, parietotemporal region, and occipital bone. For each configuration, the presence of significant sex differences in shape and size was tested. Principal component analysis (PCA) was applied to explore the shape variation. The classification power of size and shape was tested using discriminant analysis and k-means clustering. The neurocranium shows significant sex differences in shape and size. The parietotemporal region is the most dimorphic neurocranial part in size and the frontal bone is the most differing one in shape. The size of the parietotemporal region and frontal bone classifies correctly more than 80% of the crania. The discrimination ability based on shape is rather low as the highest values of about 70% are obtained for the frontal and occipital bone. The PCA plots show large overlapping of the male and female crania. It can be inferred that the sex-specific size differences in the neurocranium are more important than the shape differences.
摘要:
性别鉴定是骨骼遗骸法医分析的主要步骤。性别估计方法的准确性在很大程度上取决于目标解剖区域所表现出的性二态性。该研究旨在评估神经颅骨的形状和大小的性二态性,并比较不同颅骨区域的形状和大小的潜力,以正确分类男性和女性颅骨。这项研究是在373名保加利亚成年人(161名男性和212名女性)的计算机断层扫描图像上进行的。获取了32个地标的三维坐标。地标以4种构型排列:神经颅骨,额骨,顶颞区,和枕骨.对于每种配置,在形状和大小方面存在显著的性别差异。主成分分析(PCA)用于探索形状变化。使用判别分析和k均值聚类测试了大小和形状的分类能力。神经头颅在形状和大小上显示出明显的性别差异。上颞叶区域是大小最二形的神经颅部分,额骨是形状最不同的部分。顶颞区和额骨的大小可以正确分类超过80%的颅骨。基于形状的辨别能力相当低,因为额骨和枕骨获得了约70%的最高值。PCA图显示了男性和女性颅骨的较大重叠。可以推断,神经颅骨的性别特定大小差异比形状差异更为重要。